fix(memory): constrain search_nodes query length - #4662
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The search_nodes tool accepted an unbounded query string (per modelcontextprotocol#3537, official servers should constrain string parameters). An oversized query costs an O(graph) scan per call with no value. Cap it at 2048 chars via an exported SearchNodesQuerySchema, and add vitest coverage for the boundary (at-limit accepted, over-limit rejected, non-string still rejected). Signed-off-by: fei <204683769+feiiiiii5@users.noreply.github.com>
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Summary
Add a length constraint to the memory server's
search_nodesqueryparameter, per #3537 (official servers' string parameters lackmaxLength/patternconstraints, creating DoS and malformed-input risk).Root Cause
src/memory/index.tsregisterssearch_nodeswithquery: z.string()— completely unbounded. Each call with an oversized query still triggers a full O(graph) scan over every entity name, type, and observation, for no retrieval value.Fix
Follows the pattern in #4282 (time server string constraints):
SEARCH_QUERY_MAX_LENGTH = 2048named constant — generous for real retrieval queries, hard cap against abuse.SearchNodesQuerySchema(z.string().max(...)) used by the tool'sinputSchema, so the constraint is testable directly.Scope kept to
queryas named in #3537's memory-server finding; other parameters can follow in separate PRs.Test
New
src/memory/__tests__/search-nodes-schema.test.ts(vitest, per CONTRIBUTING):npm testinsrc/memory: 4 test files, 54 tests passed (including the 4 new cases).Diff scope
src/memory/index.ts(+8/-1), new test file (+25).